Drilling jig



` Ju1y10,1-945. l vF. HCAMERON 2,380,291

DRIQLING JIG Filed Dec. 17, 1943 hole.

UNIT-EoisrAT-es 'PATENT oFFlcE FredfHCamerom Corry, Pa., assignor to'Aero l* Y Y i Supply Mfg. Co. Inc., CorryPa. j Application December 17, 1943, Serial'No. 514,682

This invention relates to drilling jigs. y

An object of thisl invention is to provide ajig or `chuck whereby 1: a transversey hole may be drilled through a bolt or'similar round threaded article' at a specific location, the jig or chuck being so constructed that the drill willnot cause a 4burr to occur at one or bothends of the drilled This invention contemplates the provision of a pair of jaws Apivotally lconnected together and each jaw having a changeable insert so that the device may be usedfor'diiferent sizes of articles, the jaws having aligneddrill guide openings and the inserts having openings registering with the l drill guide opening. Each insert is formed with drawing, wherein is shown an embodiment of the invention, but it is to be understood `that changes', .variations Vand modifications vmay be resorted to which fall within 'the scope of the invention asl claimed. v

In the drawing:

' Figure 1 is a detail side elevationpartlybroken away and in section ofa drilling jig orchuck constructedA according to an embodiment of this invention,

Figure 2 is a plan view of the device, Figure 3 is a sectional view taken on the line 3-3 of Figure 2,

Figure 4 is a fragmentary sectional View taken on the line 4--4 of Figure 2, and

Figure 5 is a fragmentary top plan of the upper or inner side of the lower jaw. v

Referring to the drawing, the numerals I0 and Il designate generally a pair of work clamping. jaws, the jaw I0 being a lower stationary jaw and the jaw II being anupper and movable or pivoted jaw. 'I'he lower jaw I0 has projecting from the body I2 thereof a plurality of supporting feet I3, and a pair of upwardly projecting ears I4 extend upwardly from one end of the body I2. The upper or movable jaw II is of substantially rectangular configuration in plan cludes a shank 24'on which a nut 25 is threaded.

aclaims. (01917-62) l p y `and is Vformed at'the rear or one end thereof with a projecting lug l5 through which apivot member I6 engages. The pivot member I6 also engages through the-two ears I4 andis firmly secured against endwise movement'with respect to the vlug I5 by means of'av setfscrew I'I'. Y

AThe upper-jaw II is adapted to be held in a clamping position with respectto the lower jaw I0 by means of an eye bolt I8. includes an eye I9 which is disposed in a slot 20 formed in the body 2| of lthe jaw II at the end opposite from the lug I5. A shaft or pin 22 is secured in the body 2I across the opening or slot 20 and loosely engages through the eye I9. The

pin 22 is` held against endwise movement yby means of a set screw 23. -The eye bolt I3 inwhen in clamping position engages against the underside ofthe body I2.

The lower jaw body I2 is formed with a transversely extending `channel or recess 2l and the upper jaw body 2| is formed with a complementary orfconfronting recess 23. An insert 29 is mounted in the recess '21 of the lower jaw and a complementary or confronting insert 3!) is mounted in the recess 2B. The insert 29 is formed with a transversely arcuate groove 3l lin the upper side vthereof and the insert 30 is formed witlra transversely arcuate groove 32 which confronts the groove 3|, The two grooves 3| and 32 as shown in Figure 5 are formed with .a threaded portion 33 for a portion of the length of the insert so that a bolt B may have the shank S thereof disposed within the confronting grooves 3| and 32 and the threads of the bolt shank will engage the complementary threads of the inserts. I

The insert 29 is removably secured in the recess 21 by `means -of cap screws or fastening members 34 and the insert 30 is removably mounted in the recess 28 by means of fastening devices 35. The insert 29 is initially positioned 'within the recess 21 by means of a pair of posi- The eye bolt I8' The upper clamping jaw II has extending downwardly thereinto a plug 38 which may be of a metal tempered to a harder degree than the upper jaw Il and the plug 38 is formed with a central bore or drill guiding opening 39. The insert 30 is formed. with a drill guiding opening 40 aligning with the opening 39 so that a drill may be extended down through the guide opening 39 and the opening 4i! for contact with the shank S of the bolt.

The lower jaw body I2 is formed with a drill guiding opening 4I aligning axially with the opening 39 and the insertJ 29 is also formed with a drill guiding opening 42 registering with the opening 4l and aligning with the openings 40 and 39.

In the use and operation of theV drill jig or chuck hereinabove described, the upper jaw l! is moved upwardly to an open position, the nut 25 being unthreaded on the shank 24 and the eye bolt I8 swung outwardly to a position disengaged from the lower jaw I0. The bolt shank S is then seated in the lower groove 3l with the threads of the Shank S engaging the threads 33 of the lower insert 29. The head of the bolt is preferably positioned in contacting relation with the adjacent end of the insert 29 and the upper jaw II is then swung downwardly and the eye bolt I8 swung inwardly with the shank 24 engaging in the slot 2G, of the lower jaw I0.

1 Before the nut 25 is turned to a fully clamping position, the bolt B is turned slightly to iirmly tighten the bolt between the two inserts 29 and 39. The nut 25 may then be tightened so that the bolt B will be held against rotation between the two jaws l and Il. The drill is then extended downwardly through the guide openings 39 and 40, drilling a hole in the shank S in alignment with the holes of the inserts.

By providing the two inserts 29 and 30 with complementary threaded portions, the threaded portions of the inserts will interengage with the threads of the bolt shank so that when the drill cuts through the shank of the bolt the snug and tight engagement oi the inserts with the'threads of the bolt will eliminate any burrs in the opposite ends of the hole which is formed diametrically through the shank of the bolt..

The drill guiding openings in the upper and 59 lower jaws and in the inserts are positioned at a predetermined distance with respect to one edge of each jaw so that when the bolt is tightly gripped between the jaws, and the head of the bolt contacts with the adjacent ends of the inserts, the hole formed through the shank of the bolt will be at the desired position with respect to the end of the shank of the bolt. This hole in the bolt is provided for receiving a cotter pin,

locking wire or other means which is correlated with a slotted nut for locking the nut on the shank of the bolt.

Where it is desired to drill holes through diiferent sizes of bolts, diierently grooved inserts may be mounted in the channels or recesses 21 and 28 of the two jaws and the inserts may be of any desired length, that is, the inserts may lo'either be ilush with the adjacent sides of the two jaws or may project from the adjacent sides of the jaws, depending upon the length of the bolt to be drilled and the position of the hole in the bolt shank.

By providing a. drill jig or chuck as hereinabove described, all burrs normally formed in drilling a bolt diametrioally therethrough, particularly through threads, are eliminated so that these burrs will not tear the threads on the nut which is mounted on the bolt shank and will not damage any of the threads on the bolt shank inwardly from the end of the shank, as is the case where a burr is formed and the nut pulls the burr from the shank and drags the metal along the threads as the nut is threaded on the bolt shank.

What I claim is: 1. A drill jig or chuck for drilling an article without creating a burr, comprising a pair of ar- 30 ticle clamping jaws, each jaw having a recess therein, confronting article gripping inserts in said recesses, each insert having a groove formed with threads for a portion of the length thereof, means securing said inserts in said recesses, positioning means for accurately positioning said inserts in said recesses, and means for holding said jaws in clamping position,v said jaws having axially aligned drill guide openings and said inserts having openings registering with said jaw openings.

- 2. A drill jig or chuck for drilling an article without creating a burr, comprising a pair of article clamping jaws, each jaw having a recess therein, confronting article gripping inserts in said recesses, each insert having a groove formed with threads for a portion of the length thereof, means securing said inserts in said recesses, a positioning pin carried by each jaw engageable with an inert for accurately positioning said insert in a recess, means for holding said jaws in clamping position, said jaws having axially aligned drill guide openings and said inserts having openings registering with said jaw openings, one of 'said jaws including a tempered plug formed with a drill guiding opening aligning with the opening of the other jaw.

' FRED H. CAMERON. 

